ZrNbCN thin films as protective layers in biomedical applications

This paper reports an investigation on the characteristics of a novel quaternary protective coating to be used in biomedical applications, namely ZrNbCN, with Nb as alloying element. The coatings were prepared by the reactive magnetron sputtering method. Different film compositions were obtained by varying the total reactive gas (CH4 + N2) flow rate, while maintaining constant the CH4/N2 flow ratio. ZrCN films were also prepared as reference coatings. The coatings, with two different non-metal/metal ratios, were comparatively investigated in terms of the elemental composition, chemical bonds, corrosion resistance, and biological properties. The results indicated that the corrosion resistance and biocompatibility of the films depend on the composition. Improved corrosion behavior and biocompatibility were found by adding alloying elements (Nb) to the basic ZrCN structure. A better corrosion resistance and higher cell viability were observed for an increase in non-metal/metal ratio in ZrNbCN coatings.